滚动字幕条件下的新闻视频检索研究

Research on News Video Search Under the Condition of Scroll Captions

通过研究滚动字幕存在的条件下新闻标题字幕的显示特点,提出了一种相邻行灰度差极大值结合帧间差新闻标题字幕定位方法,该法包括灰度化预处理、计算相邻行灰度和之差、求出大于阈值的行灰度和之差的极大值、帧间相减等步骤,该方法简单有效,可以很好地消除滚动字幕条的影响,正确定位出新闻视频标题字幕。

This thesis brings up a method to locate News captions by combining maximum of grayscale variance between adjacent rows with the frame difference. This method includes several approaches： pre-treatment of getting it gray, calculating the difference of grayscale sums between adjacent rows, calculating the maximum difference of grayscale sums between adjacent rows which is bigger than the threshold, intra-frame subtraction and so on. This method is simple and efficient, it can eliminate the affects from scroll captions and locate the news video captions correctly.